INSTALLATION AND
OPERATING INSTRUCTIONS
FOR
THE HARDY
OUTSIDE WOOD
BURNING HEATER
Model – H2, H3, H4 & H5
HARDY MANUFACTURING
COMPANY, INC.
12345 ROAD 505
PHILADELPHIA, MS 39350
PHONE: (601) 656-5866
FAX: (601) 656-4559
www.hardyheater.com
Rev. 03/13
THIS PAGE INTENTIONALLY LEFT BLANK
INTRODUCTION
Thank you for purchasing the original all stainless steel Hardy Outside Wood-Fired
Hydronic Heater. It represents the result of many years of Hardy experience and the
input of Hardy customers in the production of a top quality heater. With the purchase of
this Hardy Hydronic Heater, you can now appreciate the high degree of craftsmanship
and reliability that have made The Hardy the leader in the Outside Wood-Fired
Hydronic Heater field. This manual will provide you with a good basic understanding of
the installation and operation of this heater.
THIS MANUAL INCLUDES IMPORTANT SAFETY INFORMATION.
Your new heater should have the following:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
Owner’s manual complete with Installation
and Hook-Up Instructions
Warranty & Return Warranty Card
A tube of silicone (located in the firebox for shipping)
Smoke stack and condenser tank stack both
with trim (located in the firebox for shipping)
H2 & H3 has two I-beams and three cast iron grates (located in the firebox)
H4 & H5 has one I-beam, two channels and six grates (located in the fire
box)
Shovel (located in the firebox for shipping)
Stainless steel panel and insulation that will be
located between the firebox door & ash door
after installation of the heater
Stainless steel flame baffle (15” x 10”). Only for
use on Hardy model H4 & H5
Should your heater not have any of these items or if you have any questions regarding
the operation or maintenance of your heater, please consult you local Hardy dealer.
Again, thank you for purchasing a Hardy Outside Wood-Fired Hydronic Heater.
Sincerely,
Frank L. Moore
President
Hardy Manufacturing Company, Inc.
(MODEL H2, H3, H4, & H5)
i
Please fill in the following information
Hardy Model
Serial Number
Date of Purchase
Date of Installation
Dealer Purchased from
Dealer Address
Dealer Phone Number
HARDY MANUFACTURING COMPANY, INC.
12345 ROAD 505
PHILADELPHIA, MS 39350
PHONE: (601) 656-5866
www.hardyheater.com
(MODEL H2, H3, H4, & H5)
ii
SAFETY PRECAUTIONS
WARNING
Do not operate this equipment for other than its intended purpose nor other
than in accordance with the instructions contained in this manual and all other
instructions accompanying the unit. For units covered by this instruction book, it is
important to observe safety precautions to protect yourself from possible injury. Among
the many considerations, you are advised to:








Observe all safety stickers on the unit.
This unit must be wired by a qualified electrician in accordance with the National
Electrical Code.
Never use any type of petroleum product, petroleum based product, charcoal
starter, lighter fluid, or any other flammable accelerant to start your unit.
Always open the ash door (bottom) before you open the firebox door (top).
Never leave the doors open, always latch the doors securely.
Always use proper care when installing, operating and maintaining the unit.
Do not modify the unit.
Do not substitute repairs which can be provided by your dealer, distributor, or
Hardy Manufacturing Company.
Failure to heed this warning or any additional warnings on the unit may result in an
accident causing personal injury.
Safety Labels and Rating Labels
Read all safety labels on this unit
5” X 3.5”
H2-1-17
120,000
(MODEL H2, H3, H4, & H5)
iii
2.5
Safety Labels
Read all safety labels on this unit
Name Plate Supplement
5” X 10” (not shown actual size)
(MODEL H2, H3, H4, & H5)
iv
Safety Labels
Read all safety labels on this unit
Heater Wiring Diagram
3” X 8”
HARDY MODELS H2, H3, H4 & H5
HEATER WIRING DIAGRAMS
CONNECTION DIAGRAM
L1
LIQUID LEVEL
WATER VALVE
SWITCH
L2
GROUND FAULT
CIRCUIT
R
INTERRUPTER
RELAY
R3
PUMP MOTOR
M
RELAY OPTIONAL
PUMP MOTOR
R3
SECOND
HEATING
M
ZONE
DAMPER BLOWER
MOTOR
M
DAMPER
AQUASTAT
DAMPER SOLENOID
SCHEM ATIC DIAGRAM
L1
L2
GFCI
WV
LLS
R
4
6
PM
R3
4
6
PM
R3
T1
BM
SOL
LEGEND
GFCI
GROUND FAULT CIRCUIT INTERRUPTER
LLS
LIQUID LEVEL SWITCH
WV
WATER SOLENOID VALVE
(OPTIONAL ON H3 & H5)
R3
CIRCULATOR PUMP RELAY
PM
WATER CIRCULATOR PUMP
T1
DAMPER AQUASTAT
BM
DAMPER BLOWER MOTOR
SOL
DAMPER SOLENOID
R
LOW WATER LIGHT
(MODEL H2, H3, H4, & H5)
v
Safety Labels
Read all safety labels on this unit
Warning label for Condenser Vent
5” X 3”
Back Door label
5” X 3”
(MODEL H2, H3, H4, & H5)
vi
Safety Labels
Read all safety labels on this unit
Warning label on front between doors
4” X 2 3/4”
Field wiring label
2 3/4” X 1”
Hot water label
2 3/4” X 1”
(MODEL H2, H3, H4, & H5)
vii
THIS PAGE INTENTIONALLY LEFT BLANK
(MODEL H2, H3, H4, & H5)
viii
OUTDOOR WOOD HEATER BEST BURN PRACTICES
1. Read and follow all operating instructions supplied by the manufacturer.
2. FUEL USED: Only those listed fuels recommended by the manufacturer of your unit.
Never use the following: trash, plastics, gasoline, rubber, naphtha, household
garbage, material treated with petroleum products (particle board, railroad ties and
pressure treated wood), leaves, paper products, and cardboard.
3. LOADING FUEL: For a more efficient burn, pay careful attention to loading times and
amounts. Follow the manufacturer’s written instructions for recommended loading
times and amounts.
4. STARTERS: Do not use lighter fluids, gasoline, or chemicals.
5. LOCATION: It is recommended that the unit be located with due consideration to the
prevailing wind direction.
• Furnace should be located no less than 100 feet from any residence not served by
the furnace.
• If located within 100 feet to 300 feet to any residence not served by the furnace, it
is recommended that the stack be at least 2 feet higher than the peak of that
residence.
Chimney Height Installation Scenario
Residence not
served by furnace
2 feet
Residence
served by furnace
Chimney height
should be 2 feet above roof line.
Minimum of 100 feet
6. Always remember to comply with all applicable state and local codes.
Outdoor Furnace Manufacturers Caucus
(MODEL H2, H3, H4, & H5)
ix
THE HARDY OUTSIDE WOOD-FIRED HYDRONIC HEATER
How does an The Hardy heat my home?
The Hardy Outside Wood-Fired Hydronic heater is designed to save the most energy
and provide the most comfortable heating available. It heats your home by heating a
stainless steel tank filled with water, which surrounds the firebox of the outside heater.
The heater is basically a non pressurized boiler with an atmospheric vent. This hot
water is then circulated through underground hot water pipes to a water coil inside your
existing central duct system. The Hardy Hydronic Heater can be connected to any
existing hydronic heating system that operates at 180 degrees or less.
How does The Hardy heat water for household use?
A cold water supply line goes to the outside heater. This water line also keeps the
water tank of the heater full. The heater only takes on water as it evaporates. The cold
water line is connected to a heat exchanger which lies inside the water reservoir of the
outside heater. The pressure on the supply line forces water through the heat
exchanger when you open a hot water faucet inside your home. As this water passes
through the heat exchanger it picks up the heat from the hot water that surrounds it
and then goes to the cold side of your water heater. This means your water heater will
take on hot water. This water is not contaminated with the water that passes through
your heater and coil to heat your house.
How do the thermostat controls work?
The only visible addition to the heating system inside your home is the thermostat
which is located near the existing thermostat. The two thermostats are installed so that
if the outside wood heater is not in operation, your existing unit will automatically take
over to maintain the household temperature. The wall thermostat which regulates the
heat from the outside heater performs two functions; when it senses the need for heat,
it turns the water pump on to circulate the hot water through the coil and also turns the
blower on inside your central unit to force air across the hot coil. This forces hot air
into your central duct system. The outside heater has a hot water thermostat which
senses the water temperature of the unit. If the water is not as hot as the thermostat
setting then the combustion air intake is automatically opened and remains open until
such temperature is attained.
Where should The Hardy be located?
The outside unit should be located at least 10 feet from your home so that all fire
danger is removed from your home. The unit may be installed as much as 100 feet
away and still heat your house and hot water. If the unit is located more than 100 feet
away, you may experience some heat loss on the water going to your hot water heater.
Locate the heater where it will be convenient for refueling and wood storage. All water
and power lines are installed underground between the house and the heater.
(MODEL H2, H3, H4, & H5)
x
TABLE OF CONTENTS
SECTION I:
General Information
1-1 Specifications ............................................................1-2
1-2 Heater Component Parts Model H2 ............................. 3
1-3 Heater Component Parts Model H3 ............................. 4
1-4 Heater Component Parts Model H4 ............................. 5
1-5 Heater Component Parts Model H5 ............................. 6
SECTION II:
Installation of Heater
2-1 Location of Heater .....................................................7-8
2-2 Chimney Connection .................................................... 8
2-3 Hull Removal ................................................................ 9
2-4 Set-Up of Grates ........................................................ 10
2-5 Location of Plumbing & Electrical Lines ..................... 11
2-6 Connection of Power to Heater .................................. 12
2-7 Wiring Diagram .......................................................... 13
SECTION III: Plumbing Instructions
3-1 Instructions for forced air systems ............................. 14
3-2 Location of heating coil .........................................15-16
3-3 Instructions for Hydronic systems .........................17-18
3-4 Instructions for Domestic Water on H2/H4 ................ 19
3-5 Instructions for Domestic Water on H3/H5 ................ 20
3-6 Replacing Hull ........................................................... 21
3-7 Filling the Heater with water ...................................... 22
SECTION IV: Connection to Central Heating/AC System
4-1 Connection to Central Unit
with Existing Blower Relay ...................................23-24
4-2 Connection to Central Unit
with Existing Blower Relay Diagram ......................... 25
SECTION V:
Heater Operation
5-1 Firing the Heater ........................................................ 26
5-2 Water Temperature ................................................... 26
5-3 Moisture in the Firebox .............................................. 26
5-4 Wood Usage .............................................................. 27
5-5 Improper Burning ....................................................... 27
5-6 Ash Removal ............................................................. 27
5-7 Ash Disposal ............................................................. 27
5-8 Creosote Formation and Removal ............................. 28
(MODEL H2, H3, H4, & H5)
xi
SECTION VI: Service Information
6-1 Electric Make-Up Water System ................................ 29
6-2 Water Circulation System .......................................... 30
6-3 Temperature Control System .................................... 31
SECTION VII: Heater Maintenance
7-1 Preventative Maintenance ......................................... 32
7-2 Preseason Maintenance .......................................33-34
7-3 In Season Maintenance ........................................34-35
7-4 Post Season Maintenance ......................................... 35
SECTION VIII: Appendix
8-1 General Trouble Shooting Guide ..........................36-43
8-2 Circulator Maintenance Instructions ......................44-45
8-3 Damper Solenoid Replacement Instructions .............. 46
8-4 Low Water Switch Replacement Instructions ........47-48
8-5 Draft Blower Replacement Instructions .................49-50
8-6 Automatic water fill Replacement Instructions .......51-52
8-7 Aqua stat Replacement Instructions......................53-55
(MODEL H2, H3, H4, & H5)
xii
SECTION I
GENERAL INFORMATION
1-1
Specifications
Type of fuel – Clean Seasoned Hard Wood - Clean wood means wood that has no
paint, stains, or other types of coatings, and wood that has not been treated with
preservatives, including but not limited to, copper chromium arsenate, creosote, or
pentachlorophenol.
For outdoor use only
Electrical Rating
115 VAC/ 60 HZ / 1PH
MFS-15 AMP, MCA-15 AMP
Clearance to Combustibles
Top, Rear, Sides
Chimney Connector
Front
Flooring
18”
18”
48”
Non Combustible
Water Capacity
H2 & H3 – Holds Approximately 100 Gallons of Water
H4 & H5 – Holds Approximately 130 Gallons of Water
Heater Dimensions
Description
H2 & H3 – 120,000 BTU
H4 & H5 – 180,000 BTU
Width
30”
40”
Depth
52 ½”
52 ½”
Height
59 ½”
59 ½“
Weight
650 lbs.
850 lbs.
Width
24”
34”
Depth
32”
32”
Height
36” + 8” for Grates
36” + 8” for Grates
Size OD
6”
8”
Material
Stainless Steel, Single wall
Stainless Steel, Single wall
Firebox sizes
Description
H2 & H3 – 120,000 BTU
H4 & H5 – 180,000 BTU
Chimney
Description
H2 & H3 - 120,000 BTU
H4 & H5 - 180,000 BTU
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 1
1-1
Specifications
On the front of your heater there is a nameplate. Along with other information you will
find the model number of your heater. This model number tells you what your heater
rating is and what electrical and plumbing options your heater has, use the following
list to determine this. The first section determines the rating of your heater. The second
section determines electrical options. The last section determines the plumbing
options. For example heater model number H2-1-17. The H2 designates that you have
a 120,000 BTU heater. The 1 in the second section designates that you have a
standard pump. The 1 in the last section designates that you have domestic hot water
coil. The 7 in the last section designates that you have extra ports on your heater.
Model
Electric options
Plumbing options
Heater Rating
H2 – 120,000 BTU
H3 – 120,000 BTU
H4 – 180,000 BTU
H5 – 180,000 BTU
H2-1-17
120,000
2.5
Electrical Options
Plumbing Options
0 – Without a Pump
1 – Standard Pump
2 – 2nd Pump & Relay
3 – 3rd Pump & Relay
4 – Without a Pump for Heating System
and with Circulating Domestic Hot Water
5 – With a Standard Pump for Heating System
and with Circulating Domestic Hot Water
6 – With 2nd Pump and Relay and with
Circulating Domestic Hot Water
7 – With 3rd Pump and Relay and with
Circulating Domestic Hot Water
8 - Optional External Plate & Circulator
9 - Optional automatic water fill
0 – Without Domestic Hot Water
1 – Standard Domestic Hot Water
2 – With 2nd Heat Exchanger (2nd Domestic
Hot Water or Swimming Pool heat exchanger)
3 – With 3rd Heat Exchanger (2nd Domestic
Hot Water and Swimming Pool Heat
Exchanger)
4 – Extra 60’ copper in Domestic Hot Water
5 – Extra 60’ copper in Domestic Hot Water
and Swimming Pool Heat Exchanger
6 – 1” Heat Exchanger –2 – 60’ Rolls 3/4” Copper
Manifold to 1” Ports
7 – Extra Ports, 1/2”, 3/4”, 1”, etc.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 2
1-2
Heater Component Parts Model H2
1
4
2
12
3
11
5
6
16
5
15
17
8
9
7
18
10
13
14
19
20
21
24
20
25
22
23
27
22
38
28
29
37
30
31
26
32
39
33
34
21
36
6
35
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
Part No.
600.10
810.00
1100.28
607.37
602.16
603.40
602.32
603.08
607.00
605.00
1100.00
400.75
600.57
600.30
604.32
607.30
604.16
2000.48
2000.08
603.32
607.12
502.60
502.50
810.10
2004.40
810.15
1100.30
2000.52
2001.05
2004.00
2004.16
3200.12
3200.16
2002.16
2004.28
607.42
2004.04
2004.08
2004.52
Description
1/2” Brass Elbow
1/2” Overflow Pipe
Low Water Switch
Vacuum Relief Valve
3/4” Brass Tee
3/4” x Close Brass Nipple
3/4” x 3/4” x 1/2” Brass Tee
1/2” x Close Brass Nipple
1/2” Brass Ball valve
1/2” x 1/4” Brass Bushing
Electric Solenoid Valve
3/8” OD Pex fill line
3/8”comp x 1/4” mpt elbow
3/4” Brass Elbow
3/4” Brass Cap
3/4” T & P Valve
1/2” Brass Cap
1/2” Well Fitting
Honeywell Aqua stat
3/4” x 6” Brass Nipple
3/4” Brass Ball Valve
3/4” SS flange
Taco 009 SS Circulator
3/4” T&P Relief Pipe
Wire Connectors
5/8” Clamp
Low Water Light
Honeywell Relay
Damper Solenoid
GFCI Receptacle
Receptacle box 2 1/8” deep
Jack Chain
Key Ring
100 CFM Blower / Lid
Plastic Romex Connector
3/4” Boiler Drain
3’ 3 Wire Power Cord
8’ 2 Wire Power Cord
Electrical Mounting Panel
5
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 3
1-3
Heater Component Parts Model H3
29
3
1
2
7
7
9
8
6
11
10
12
15
11
13
14
27
16
13
17
28
26
19
18
20
21
22
23
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
Part No.
600.10
810.00
1100.28
602.16
603.40
600.30
604.32
604.16
2000.48
2000.08
603.32
607.12
502.60
502.50
2004.40
1100.30
2000.52
2001.05
2004.00
2004.16
3200.12
3200.16
2002.16
2004.28
607.42
2004.04
2004.08
2004.52
604.00
Description
1/2” Brass Elbow
1/2” Overflow Pipe
Low Water Switch
3/4” Brass Tee
3/4” x Close Brass Nipple
3/4” Brass Elbow
3/4” Brass Cap
1/2” Brass Cap
1/2” Well Fitting
Honeywell Aqua stat
3/4” x 6” Brass Nipple
3/4” Brass Ball Valve
3/4” SS flange
Taco 009 SS Circulator
Wire Connectors
Low Water Light
Honeywell Relay
Damper Solenoid
GFCI Receptacle
Receptacle box 2 1/8” deep
Jack Chain
Key Ring
100 CFM Blower / Lid
Plastic Romex Connector
3/4” Boiler Drain
3’ 3 Wire Power Cord
8’ 2 Wire Power Cord
Electrical Mounting Panel
1/4” Brass Cap
24
7
12
25
7
5
4
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 4
1-4
Heater Component Parts Model H4
1
2
3
11
5
4
8 9
6
5
18
13
7
10
6
14
7
19
8
20
9
10
21
11
12
13
20
14
15
22
16
17
23
18
19
28
20
37
22
21
22
23
24
29
25
26
32
27
28
33
29
30
31
32
33
35
34
34
35
15
36
15
37
38
39
4
3
1
2
5
15
15 17
16
25
38
24
27
30
26
31
39
36
HARDY MANUFACTURING CO., INC
12
Part No.
600.10
810.00
1100.28
607.37
602.16
603.40
602.32
603.08
607.00
605.00
1100.00
400.75
600.57
600.30
604.32
607.30
604.16
2000.48
2000.08
603.32
607.12
502.60
502.50
810.10
2004.40
810.15
1100.30
2000.52
2001.05
2004.00
2004.16
3200.12
3200.16
2002.28
2004.28
607.42
2004.04
2004.08
2004.52
Description
1/2” Brass Elbow
1/2” Overflow Pipe
Low Water Switch
Vacuum Relief Valve
3/4” Brass Tee
3/4” x Close Brass Nipple
3/4” x 3/4” x 1/2” Brass Tee
1/2” x Close Brass Nipple
1/2” Brass Ball valve
1/2” x 1/4” Brass Bushing
Electric Solenoid Valve
3/8” OD Pex fill line
3/8”comp x 1/4” mpt elbow
3/4” Brass Elbow
3/4” Brass Cap
3/4” T & P Valve
1/2” Brass Cap
1/2” Well Fitting
Honeywell Aqua stat
3/4” x 6” Brass Nipple
3/4” Brass Ball Valve
3/4” SS flange
Taco 009 SS Circulator
3/4” T&P Relief Pipe
Wire Connectors
5/8” Clamp
Low Water Light
Honeywell Relay
Damper Solenoid
GFCI Receptacle
Receptacle box 2 1/8” deep
Jack Chain
Key Ring
130 CFM Blower / Lid
Plastic Romex Connector
3/4” Boiler Drain
3’ 3 Wire Power Cord
8’ 2 Wire Power Cord
Electrical Mounting Panel
(MODEL H2, H3, H4, & H5)
PAGE 5
1-5
Heater Component Parts Model H5
29
1
3
2
7
7
8
9
6
10
11
15
12
11
27
13
14
17
16
13
26
28
19
20
18
21
22
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
Part No.
600.10
810.00
1100.28
602.16
603.40
600.30
604.32
604.16
2000.48
2000.08
603.32
607.12
502.60
502.50
2004.40
1100.30
2000.52
2001.05
2004.00
2004.16
3200.12
3200.16
2002.16
2004.28
607.42
2004.04
2004.08
2004.52
604.00
Description
1/2” Brass Elbow
1/2” Overflow Pipe
Low Water Switch
3/4” Brass Tee
3/4” x Close Brass Nipple
3/4” Brass Elbow
3/4” Brass Cap
1/2” Brass Cap
1/2” Well Fitting
Honeywell Aqua stat
3/4” x 6” Brass Nipple
3/4” Brass Ball Valve
3/4” SS flange
Taco 009 SS Circulator
Wire Connectors
Low Water Light
Honeywell Relay
Damper Solenoid
GFCI Receptacle
Receptacle box 2 1/8” deep
Jack Chain
Key Ring
100 CFM Blower / Lid
Plastic Romex Connector
3/4” Boiler Drain
3’ 3 Wire Power Cord
8’ 2 Wire Power Cord
Electrical Mounting Panel
1/4” Brass Cap
23
7
24
12
25
5
4
HARDY MANUFACTURING CO., INC
7
(MODEL H2, H3, H4, & H5)
PAGE 6
SECTION II
INSTALLATION OF HEATER
2-1
Location of Heater
The Hardy Hydronic Heater must be located outside the building to be heated. The unit
must be located a minimum of 10 feet from the building. The unit should be installed
upon a concrete pad. There are two typical installation options that we recommend.
Option 1 has the unit installed on concrete pad with the rear of the water tank flush with
the end of the pad. We recommend the pad to be 48” wide and 53” long minimum. If
you add extra length it will allow ample concrete in front of the heater for loading wood
and removing ashes. The space between the rear of the unit and the outside cover will
allow a 4” watertight pipe or other means to insulate the plumbing and electrical lines to
run directly into the ground. The outside cover can be removed by lifting it off the water
tank on all four corners. This will allow you easy access for the connection of the
plumbing and electrical lines.
Please see the illustration below for details.
Option 1
58.000
14.000
48.000
20.000
6.000
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 7
2-1
Location of Heater (continued)
Option 2 illustrates the unit installed on a concrete pad with cut out in the pad for
plumbing and electrical lines to run through. We recommend this pad to be 48” wide by
60” long minimum. If you add extra length it will allow ample concrete in front of the
heater for loading wood and removing the ashes. The 4” watertight pipe or other
means to insulate plumbing that runs underground exits through this cut out to allow
connections to the unit. The unit sits on the pad with the rear of the water tank flush or
even with the front side of the cutout. The outside cover of the heater can be removed
by lifting it from the water tank on all four corners. This will allow you easy access for
the plumbing and electrical connections.
Please see the illustration below for details.
Option 2
60.000
14.000
48.000
20.000
4.000
6.000
2-2
Chimney Connection
Do not connect this unit to a chimney flue serving another appliance.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 8
2-3
Hull Removal
After placing your new Hardy Hydronic Heater upon the concrete pad, you are ready to
continue the installation process. There are two methods to gain access to the rear of
the heater to make plumbing and electrical connections.
The first and easiest method is to remove the screw holding the back door panel in
place. The door is easily removed by lifting up on the handle and taking it out. With the
back door removed, using a 5/16” wrench, remove the eight metal screws that are
located below the back door. There are four on each side that hold the panel in place.
After the screws are removed, the panel should come out easily and allow access to
the bottom of the unit to make plumbing and electrical connections.
The second method is the removal of the entire cover. With the back door, the
rectangular piece of stainless, insulation between the fire box and ash doors removed,
and unplug the low water light, the outside cover can be lifted up and off as seen in the
picture. To replace the cover simply repeat these steps in reverse order.
Please see the illustration below for details.
Rear View
HARDY MANUFACTURING CO., INC
Front View
(MODEL H2, H3, H4, & H5)
PAGE 9
2-4
Set-Up of Grates
On the Hardy models H2 & H3, open the firebox door and remove everything from
inside of the heater except the two I-beams and three grates. Stand the two I-beams
up on the edge and slide over against the tabs on either side of the ash pan. The
grates can now be placed on the I-beams in line and side to side. The picture below
shows the proper way for grates to be set on the I-Beams.
These grates are designed to be turned over if they warp.
On Hardy H4 & H5 models there will be two channel beams and one I-beam with the
ends cut at a 45 degree angle. There will also be six grates. Stand the channel beams
on edge with the open side to the inside, and slide them over against the sides of the
firebox. The I-beam will need to be set on edge with the longer edge on top and placed
in the center of the firebox. The grates may then be placed on either side of the I-beam
across to the channel beams, three to a side.
See the picture below for proper set-up.
There is also a stainless steel flame baffle (15” x 10”) in the H4 & H5 heaters. This
flame baffle is inserted in the firebox across the 3/4” stainless steel pipes located
directly below the smoke stack.
3 Grate Setup for H2 & H3
Flame Baffle
6 Grate Setup for H4 & H5
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 10
2-5
Location of Plumbing and Electrical Lines
The plumbing and electrical lines for your unit must be installed underground. The
water lines must be buried below the frost line to prevent freezing. The depth of the
trench varies to different regions of the country. Be completely sure about the correct
depth before the plumbing lines are installed underground. A trench must be dug wide
enough to accommodate a 4” watertight pipe or other insulation means. All plumbing
and electrical lines should be run inside the 4” watertight pipe or other insulation
means for a standard installation. If more than one zone is to be heated or more than
one location is to be heated then an additional pipe, or insulation must be installed
underground. This pipe will run from the rear of the unit to the location to be heated.
Inside the 4” watertight pipe will be the four water lines, thermostat wire, and electrical
supply wire. The listing below describes each line and their function.
1.
2.
3.
4.
5.
6.
One cold water supply line (if heater has auto fill option).
One hot water return line to water heater (if heater has internal domestic water
heat exchanger).
One water supply line to heating system.
One water return line from heating system
(All of these must be at least 3/4” pipe and
may require 1” because of longer distances
or some hydronic applications).
One 3 conductor thermostat wire.
One #12/2 W/G UF underground Romex wire.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 11
2-6
Connection of Power to Heater
This unit must be wired by a qualified electrician
in accordance with the National Electrical Code.
The #12/2 W/G UF wire is run from the electrical system in the house through the 4”
watertight pipe or other insulation means to the heater.
This wire will connect to the Ground Fault Circuit Interrupter (GFCI) on the back of the
heater.
Install a Romex Connector in the bottom of the electrical makeup box, and insert
Romex wire through this connector.
Connect the black wire to the brass screw on the line side of the GFCI receptacle.
Connect the white wire to the silver screw on the line side of the GFCI receptacle
Connect the bare copper wire to the green screw on the GFCI receptacle.
After the wiring is complete, and power is applied, check the receptacle with a circuit
tester to determine if the polarity is correct, and to make sure the ground is connected.
Press the test button on the GFCI receptacle. The reset button should pop out
indicating the interrupter is operating correctly. Push the reset button back to restore
the GFCI receptacle to normal operation. This test should be done monthly to insure
safe operation of the heater.
If moisture is allowed into the Ground Fault Circuit Interrupter box, it will have a
tendency to trip unwarranted. Measures should be taken to keep the box dry.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 12
2-7
Wiring Diagram
L1
LIQUID LEVEL
SWITCH
L2
WATER VALVE
GROUND FAULT
CIRCUIT
INTERRUPTER
Water valve
standard on
Models H2 & H4
Optional on
Models H3 & H5
R
CONNECTION DIAGRAM
PUMP MOTOR
RELAY
R3
M
RELAY
R3
OPTIONAL
SECOND
HEATING
ZONE
DAMPER
AQUASTAT
PUMP MOTOR
M
DAMPER BLOWER
MOTOR
M
DAMPER SOLENOID
L1
L2
GFCI
SCHEMATIC DIAGRAM
LLS
LEGEND
WV
R
4
R3 6
GFCI
GROUND FAULT CIRCUIT INTERRUPTER
LLS
LIQUID LEVEL SWITCH
WV
WATER SOLENOID VALVE
R3
CIRCULATOR PUMP RELAY
PM
WATER CIRCULATOR PUMP
T1
DAMPER AQUASTAT
BM
BM
DAMPER BLOWER MOTOR
SOL
SOL
DAMPER SOLENOID
R
LOW WATER LIGHT
HARDY MANUFACTURING CO., INC
PM
4 R3 6
T1
PM
(MODEL H2, H3, H4, & H5)
PAGE 13
SECTION III
PLUMBING INSTRUCTIONS
3-1
Instructions for Forced Air Systems
The pipe that will supply the heating system is connected to the under side of the
pump. This pump is located on the right hand side of the heater (noted by # 3 in
diagram.)
The pipe that will carry the return water from the heating system is connected to the
3/4” brass tee located at the bottom left hand corner of the heater (noted by # 4 in
diagram).
These two (2) lines will go to the heat exchanger coil that mounts into the duct work of
your forced air heating system. For best results connect the line from the pump to the
fitting of the heat exchanger closest to the side of the heat exchanger that the air is
leaving. Connect the return line to the heat exchanger on the side that the air is
entering.
Water pipes must be designed for hot water service (ex. copper, cpvc, or Pex.)
Pipes should be installed in a 4” watertight pipe or some other type of insulating
means to prevent heat loss from heater to heating system. Use only copper,
brass, or stainless steel fittings. Do not use galvanized or black iron.
Air Flow
Heater with Hull and stacks
removed to show connections.
Vertical
Flow
System
3
Air Flow
Air Must be
Filtered before
passing through
Heating Coil.
4
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 14
3-2
Location of Heating Coil
The following diagrams on this page and the following page
show various methods of installing the heating coil in a forced air system.
Return Air
Package System
Supply Air
Supply Air
Install and Insulate Heating Coil
in supply side of system
and in a protected environment
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 15
3-2
Location of Heating Coil (continued)
Air Flow
Supply
Return
Vertical
Flow
System
Air Flow
Air Must be
Filtered before
passing through
Heating Coil.
Horizontal Flow System
Air Flow
Return
Air Must be
Filtered before
passing through
Heating Coil.
HARDY MANUFACTURING CO., INC
Supply
Air Flow
(MODEL H2, H3, H4, & H5)
PAGE 16
3-3
Instructions for Hydronic systems
The preferred method for connecting the Hardy Hydronic Heater to an existing
Hydronic system is by installing a p/n 300.01- 40 plate heat exchanger with 1” fittings
into the return line of the existing boiler system. This will allow the existing boiler to
remain a pressurized system. This can be done by installing a shutoff valve and two
bypass lines in the heating systems return line. Install service valves into each of the
bypass lines. (Refer to diagram below).
Run two -1” hot water lines ( suitable for continuous flow ) from the pump and return of
the heater to the existing boiler system. Connect these lines to the plate heat
exchanger so that the water flow of the heater is opposite of that from the boiler
system. Bypass the relay on the pump to allow the pump on the heater to run
continuous.
Water pipes must be designed for hot water service (ex. copper, cpvc, or Pex.)
Pipes should be installed in a 4” watertight pipe or some other type of insulating
means to prevent heat loss from heater to heating system. Use only copper,
brass, or stainless steel fittings. Do not use galvanized or black iron.
Heater with Hull and stacks
removed to show connections.
Hardy
P/N 300.01
40 Plate Heat
Exchanger
with 1" fittings
Heat Exchanger
Existing
Boiler
Close this valve
Existing
Pump
HARDY MANUFACTURING CO., INC
Heat
Zone
(MODEL H2, H3, H4, & H5)
Heat
Zone
PAGE 17
3-3
Instructions for Hydronic systems (continued)
This unit must be wired by a qualified electrician
in accordance with the National Electrical Code.
Using a new 24 volt transformer, a new 24 volt relay, and a low voltage wall thermostat
the following wiring diagram shows how to modify the existing boiler aqua stat wiring.
By adding a normal open circuit into the existing aqua stat wiring you can leave the
boiler aqua stat set at the original factory setting. Set the new low voltage wall
thermostat approximately 3 degrees below the home heat thermostat. If the heater
were to get behind for any reason the boiler can come on and help maintain the home
temperature.
Wiring to add Hardy Hydronic Heater
to existing hydronic heating system.
EXISTING
BOILER
AQUASTAT
1
2
3
6
5
NEW ROOM
THERMOSTA T
4
8
7
NEUTRA L
120 VOLT
W
R
24 VOLT
TRA NSFORMER
40 VA
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 18
3-4
Instructions for Domestic Water on H2/H4
1. The cold water supply to your Hardy Hydronic Heater can be picked up from the
cold water line supplying your existing water heater. This can be accomplished by
inserting a tee into the existing cold water line. Directly below this tee you will need
to insert a valve to stop cold water from entering the water heater. Another cold
water supply may be used that is closer or more accessible to the heater.
2. The hot water supply line from the Hardy Hydronic Heater is connected into the
existing water heater by teeing it into the cold water supply line below the valve that
was installed in step 1. If you picked up your cold water supply elsewhere, then a
valve will need to be inserted above the tee for the hot water supply.
Water pipes must be designed for hot water service (ex. copper, cpvc, or Pex.)
Pipes should be installed in a 4” watertight pipe or some other type of insulating
means to prevent heat loss from heater to heating system. Use only copper,
brass, or stainless steel fittings. Do not use galvanized or black iron.
!
Heater with Hull and stacks
removed to show connections.
DANGER
Water Temperature
over 125 degrees
can cause severe
burns instantly
Cold Water Supply
Close this
valve.
Hot Outlet
Cold Inlet
Water
Heater
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 19
3-5
Instructions for Domestic Water on H3/H5
A plate heat exchanger and pump can be added to the Hardy Hydronic Heater to add
domestic hot water to the Models H3 & H5. This plate heat exchanger will provide
preheated water to the domestic hot water. The preferred method is to mount a plate
heat exchanger at the water heater and connect it as shown in the following diagram.
The pump will circulate heater water through the plate continuously. The cold water
supply will need to be connected to the opposite side of the plate heat exchanger and
flowing in the opposite direction for maximum efficiency. The alternate method would
be to mount the plate heat exchanger on the back of the heater and connect the water
heater to the plate the same way as in the preferred method with counter flowing
waters.
Water pipes must be designed for hot water service (ex. copper, cpvc, or Pex.)
Pipes should be installed in a 4” watertight pipe or some other type of insulating
means to prevent heat loss from heater to heating system. Use only copper,
brass, or stainless steel fittings. Do not use galvanized or black iron.
!
Heater with Hull and stacks
removed to show connections.
DANGER
Water Temperature
over 125 degrees
can cause severe
burns instantly
Cold Water Supply
Close this
valve.
H300.02
20 Plate
Heat Exchanger
w/ 3/4" fittings
HARDY MANUFACTURING CO., INC
Hot Outlet
Cold Inlet
Water
Heater
(MODEL H2, H3, H4, & H5)
PAGE 20
3-6
Replacing Hull
If you removed the hull to aid in plumbing the back of the heater it is time to place the
hull back on the heater. The space between the smoke stack ring and outside cover
will need a bead of silicone applied to fill any openings. The condenser tank will also
need to be sealed in this manner. The application of silicon to these openings is
illustrated by the diagram and pictures below. After these steps, you can install the
smoke stack. The trim should slide down the smoke stack until it sits on the outside
cover. The condenser stack must also be installed in the condenser tank opening. The
trim should slide down the condenser stack until it sits on the outside cover. You
should have a piece of insulation and a stainless steel plate that you removed from the
inside of the firebox earlier. This will install between the firebox door and the ash door.
The insulation fits between the doors and the stainless steel plate will slide behind the
door frames across the outer hull.
Do not seal the condenser tank to the condenser tank stack. This is the water
tank vent and must not be sealed.
Smoke stack ring
Smoke Stack and
Collar.
Condenser tank
Condenser Stack
and Collar.
Do not seal Condenser Stack
To Condenser Tank.
Seal perimeter of Smoke Stack ring
to Heater Hull using Silicone Sealant.
Seal perimeter of Condenser tank
ring to Heater Hull using Silicone
Sealant.
Do not fill past
this point.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 21
3-7
Filling the Heater with Water
The Heater must be filled with water before starting a fire.
There are certain parts of the country that have high enough levels of chloride in the
water to be harmful to stainless steel tanks. Even though the USDA allows up to 250
parts per million of chloride (salt) in the water as acceptable for drinking, experience
has shown that chloride levels as low as 45 parts per million will eventually cause
stress corrosion cracking in stainless steel tanks when water is heated. It is therefore
required to use rain water, bottled water, or your water supply with chloride content of
less than 15 parts per million. Call your Hardy dealer to get a chloride test on your
water supply.
Fill your heater with water through the condenser stack opening or when you supply
power to the heater if the heater has the automatic fill option it will fill itself. If the
chloride content of your local water supply exceeds the specifications mentioned
above and necessitates the use of bottled or rain water, please do so to maintain the
warranty of your heater.
There is a low water switch located in a fitting on the back of the heater. This low
water switch operates a low water warning light and automatic water fill solenoid if your
heater has the automatic fill option.
Do not fill past
this point.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 22
SECTION IV
CONNECTION TO CENTRAL HEATING/AC SYSTEM
4-1
Connection to Central Unit with Existing Blower Relay
This unit must be wired by a qualified electrician in accordance with the National
Electrical Code.
Turn off all power going to your central air handler system.
You will need to add a double pole / double throw relay to your central air handler.
You will also need a heat only thermostat added to the wall, preferably next to the
existing thermostat. Run a two (2) conductor thermostat wire from the air handler to the
new heat only thermostat that was added to the wall. The normal colors for this wire
are red & white. You will also need a three (3) conductor thermostat wire running from
the air handler to the outside wood heater. The normal colors for this wire are red,
white, & green.
NOTE: If you are not familiar with the control circuit of your central unit, do not continue
beyond this point. Call a heating and air conditioning serviceman to complete the
wiring. Improper wiring can cause excessive electrical usage or cause your blower
motor to over heat and burn out.
Remove the cover on the new home heat thermostat to mount it on the wall. There is a
round dial visible with an adjustable pointer. This is the heat anticipator. The dial also
has a series of numbers. The pointer must be set to the highest number on the dial. On
the Honeywell model #(t 822-1016), the pointer is turned counter clockwise as far as it
can go. On the thermostat connect the red wire to the screw terminal marked R and
the white wire to the screw terminal marked W.
At the heater, connect the white wire to terminal 8 of the water pump relay (R-3).
Connect the red wire to one side of the low temperature sensor (the round disc with
two terminals under the insulation near the center of the heater approximate 12” from
the top). This is an option that prevents the pumping of water less than 100ºF but is not
required. If you elect not to use this option, then only a two wire conductor is required,
bypassing the low temperature sensor. Connect a jumper wire from the other side of
the low temperature sensor to terminal 7 of the water pump relay (R-3) and also
connect the green wire to terminal 7 of R-3. If only two wires are used then one is
connected to terminal 7 and the other to terminal 8.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 23
4-1
Connection to Central Unit with Existing Blower Relay (continued)
This unit must be wired by a qualified electrician in accordance with the National
Electrical Code.
At the air handler inside, find the red wire going from the air handler control wiring to
the original wall thermostat. Cut this wire and connect the end that is going to the wall
thermostat to terminal # 2 on the new relay. The end of the red wire that is still
connected to the control wiring of the air handler will need to be connected to terminal
# 1 along with the new red wire that is going to the new heat only wall thermostat.
Locate the Green wire going from the central air handler control wiring to the original
wall thermostat. Cut this wire. Connect the end of the green wire that is going to the
original wall thermostat to terminal #5 of the new relay. Connect the end of the green
wire that is still connected to the central air handler control wiring to terminal #4.
Connect the white wire going to the new heat only thermostat to the red wire going
outside to the wood heater. Take the green wire that is going outside to the Hardy
Hydronic Heater and along with a short jumper wire (appx. 3” - 4” long) connect to
terminal #7 on the new relay that was added to the air handler. Connect the other end
of this jumper wire to terminal #6 of the relay.
Locate the low voltage transformer that is providing you with 24 volt power. Find the
common lead of this transformer and connect a wire to this lead and to terminal #8 of
the new relay along with the white wire going outside to the Hardy Hydronic Heater .
If all connections are made properly and the water in the Hardy Hydronic Heater is hot,
the unit should be ready for operation.
NOTE: This is a general diagram. You may have to make various changes according
to how your unit is wired. Insure that the compressor on a heat pump or A/C unit does
not run when the wood system is running. Insure that the gas burner, oil burner, or
electric elements do not come on when the wood system is running. Insure that only
one speed of the blower motor can be energized at one time. If more than one speed
is energized at the same time, the blower motor will burn out. Insure that the volt amp
rating of the existing 24 volt transformer is not exceeded when the relays in the Hardy
Hydronic Heater system are energized.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 24
4-2
Connection to Central Unit with existing Blower Relay Diagram
CONNECTION DIAGRAM
EXISTING
THERMOSTAT
EXISTING
T RANSFORMER
L1
24 VOLTS
L2
EXISTING
BLOWER RELAY
R
R
C
C
W
W
G
G
1
3
NEW
THERMOSTAT
2
4
6
5
NEW
RELAY
8
7
LOW VOLTAGE FIELD WIRING
1
3
2
4
CIRCULATOR
PUMP RELAY
6
5
8
7
LOW
TEMPERAT URE
SENSOR
SCHEMATIC DIAGRAM
TC
L1
24V
115V
L2
R1
TG
TR
4
R2
5
L EGEND
R1
EXISTING BLOWER RELAY
R3
PUMP CONTROL RELAY
R2
NEW CONTROL RELAY
T2
NEW THERMOSTAT
LTS
LOW TEMPERATURE SENSOR
FS
EXISTING THERMOSTAT
TC
TERMINAL STRIP "C" CONNECTION
TR
TERMINAL STRIP "R" CONNECTION
TG
TERMINAL STRIP "G" CONNECTION
R
EXISTING THERMOSTAT CONNECTION
G
EXISTING THERMOSTAT CONNECTION
R2
6
1
T2
LTS
8
7
R2
R3
2
8
7
QUICK CONNECT TERMINALS
FS
R
HARDY MANUFACTURING CO., INC
R2
G
(MODEL H2, H3, H4, & H5)
PAGE 25
SECTION V
HEATER OPERATION
5-1
Firing the Heater
Hardy Manufacturing Company Inc.’s recommended fuel for the Hardy Hydronic Heater
is seasoned dry hard wood. Green wood or wet wood is not recommended for use in the
Hardy Outside Wood-Fired Hydronic Heater.
Never burn the following: trash, plastics, gasoline, rubber, naphtha, household
garbage, material treated with petroleum products (particle board, railroad ties,
and pressure treated wood), leaves, paper products, and cardboard. Never use
starters: Lighter fluids, gasoline, or chemicals.
Once the Hardy Hydronic Heater has been filled with water, you can build a fire. Plug
the two (2) wire power cord into the GFCI receptacle in the back of the heater, this
should open the draft damper and turn on the draft blower. You build a fire in the Hardy
Hydronic Heater the same way you would in any other wood heater. Start out with small
split dry wood. Once you have the small wood lit gradually add more split wood and
gradually increase the size of the wood. Once a bed of coals has been established you
can use larger wood.
5-2
Water Temperature
Mounted on the back of the heater is an aqua stat that controls the draft system of the
heater to maintain a preset temperature. When the fire has heated the water in the tank
to the set aqua stat temperature, normally around 170 to 175 degrees Fahrenheit, the
draft damper and blower will shut down. This allows the fire to smother down to a
smoldering stage. As heat is used and the water temperature drops below the set
temperature the draft damper and draft blower will reenergize to build the fire back to a
heating stage.
Never set this aqua stat below 140 degrees, (this would allow the heater to sweat)
or above 180 degrees (this would bring the heater to close to a overheating point).
5-3
Moisture in the Firebox
During startup of a new heater or the first time you operate an existing heater each year,
you will probably notice moisture in the firebox. This is normal and should not cause
alarm. If after a few days of operation a high moisture content is still evident the heater
should be shut down and checked for leaks.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 26
5-4
Wood Usage
Any fuels other than those specified will result in poor and erratic heater performance.
This heater is designed to use a minimum amount of fuel but as with any heater of this
type fuel usage is based upon the load and temperature requirements. Refer to the
troubleshooting section located in the appendix for problems associated with excessive
fuel usage or poor heater performance.
5-5
Improper Burning
Improper burning during the normal operation of the heater is usually caused by lack of
combustion air or fuel in the firebox chamber. Check the air passage into the firebox
from the draft blower to make sure there is no blockage, such as ashes built up in front
of the air passage or creosote blocking the opening. Check the damper lid to make
sure it is opening properly. Check to see if the draft blower is running. Also unplug the
power cord and allow the draft blower to stop, then check the blower wheel for any
buildup that could reduce the efficiency of the draft blower. Check to see if the grates
are stopped up. Use a poker to stir the coals and create air holes in the coal bed.
Check the smoke stack for creosote build up. Also on the H4 & H5 models there is a
removable baffle plate directly below the smoke stack inside the firebox that will need
to be removed and cleaned.
5-6
Ash Removal
Ashes must be removed from inside the heater on a routine basis. Excessive ash
buildup inside the Ash box will reduce heating efficiency and can lead to premature
breakdown or warp age of the grates. When you remove the ashes, leave
approximately 1” of ash in the ash bin, this will give the coals that fall through the
grates a bed to fall on, and prevent the coals from warping the ash pan itself. The build
up of ashes in the firebox should be checked at least once a week. Allow the fire to
burn down until the grates can be seen. This insures that the grates are clear. If the
grates do warp slightly they can be flipped and allowed to straighten back out.
5-7
Ash Disposal
Ashes should be placed in a metal container with a tight-fitting lid. The closed container
of ashes should be placed on a noncombustible floor or on the ground, well away from
all combustible materials, pending final disposal. If the ashes are disposed of by burial
in soil or otherwise locally dispersed, they should be retained in the closed container
until all cinders have thoroughly cooled.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 27
5-8
Creosote Formation and Removal
When green wood is used or when wood is burned slowly, it produces tar and other
organic vapors, which combine with expelled moisture to form creosote. The creosote
vapors condense in the relatively cool chimney flue of a slow burning fire. As a result,
creosote residue accumulates on the flue lining. When ignited this creosote makes an
extremely hot fire.
The chimney connector and chimney should be inspected at least twice monthly during
the heating season to determine if a creosote buildup has occurred. If creosote has
accumulated it should be removed to reduce the risk of a chimney fire.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 28
SECTION VI
SERVICE INFORMATION
WARNING:
When working with electrical circuits, use caution to avoid electrical shock
Service on this heater should only be performed
by a qualified service technician.
6-1
Electric Make-Up Water System
LOW WATER SWITCH, P/N H1100.28
The low water switch is a horizontally mounted reed switch that has a magnet in the
floating portion of the switch. When the water level is high enough to raise the magnet
up off of the reed switch this allows the switch to break contact, and discontinue power
to the water solenoid. When the water level drops the floating portion of the low water
switch the magnet will once again come into close proximity of the reed switch and
close the contacts allowing power to be applied to the water solenoid. If this switch is
working in an opposite order to this it will need to be tightened another 180 degrees to
allow the switch to operate correctly. Never add any additional load to this switch since
it is only rated for 30 watts.
LOW WATER LIGHT, P/N H1100.30
115 VAC indicator light controlled by the float switch. The light comes on when the
water level in the heater is low.
ELECTRIC WATER SOLENOID, P/N H1100.00
115 VAC electric solenoid controlled by the float switch. This solenoid keeps the heater
full of water by allowing water to fill the heater when the float switch closes.
WATER FILTER, P/N H1100.55
A 100 mesh filter washer is located in the 1/2” x 1/4” brass hex bushing at the solenoid.
It is inserted with the cone of the screen pointed out. Filter washers are always placed
where the cone points toward the water flow. It can be removed for cleaning.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 29
6-2
Water Circulation System
LOW TEMPERATURE SENSOR, P/N H2000.36
This sensor can be wired in the home heat thermostat circuit to prevent the pump from
running when the water in the Hardy Hydronic Heater is not hot. The sensor has a set
of contacts that close when the water rises to 110ºF and open when the water drops to
90ºF.
WATER PUMP RELAY, P/N H2000.52
This is a Honeywell DPDT relay with a 24 volt coil. Terminal 4 and 6 (normally open
contacts) are used to turn on the water pump. Control voltage (24 volts) connected at
terminals 7 and 8 routed through a home thermostat energizes the relay.
WATER PUMP FOR HEATING SYSTEM, Taco 009 pump P/N H502.50
with stainless steel body. If the pump will not run, first unplug the power cord then
check the water pump relay. The relay can be bypassed by moving the wire on
terminal 6 to terminal 5 (terminals 4 to 5 is normally closed) and disconnecting the
thermostat wire from terminal 8. Now plug the power cord back in. This should supply
115 vac directly to the pump. If the pump will still not run, unplug the power cord.
Remove the four bolts holding the pump to the pump housing. Remove the cartridge
from the pump. Spin the impeller if it will not spin, replace the cartridge. If the impeller
will spin, it may have been temporarily stuck (reassemble and try again) or the problem
is the electrical winding or capacitor. Use an ohm meter to check the winding and
capacitor. If the capacitor is defective, replace it. If the electrical winding is defective,
replace the complete pump.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 30
6-3
Temperature Control System
DAMPER AQUA STAT, P/N H2000.08
This thermostat has a probe that is inserted in a well fitting in the water tank of the
Hardy Hydronic Heater . It has one set of contacts that open on a temperature rise and
close on a temperature fall. This thermostat is normally set between 170ºF to 175ºF. It
controls the damper solenoid and the forced air draft. If the damper solenoid and
forced air draft will not operate, place a jumper wire across the thermostat terminals. If
they operate when the thermostat is jumpered out, and the temperature of the water in
the heater is below the set point on the thermostat, the thermostat is defective. Do not
leave the jumper on the thermostat because the heater will overheat.
DAMPER SOLENOID, P/N H 2001.05
This solenoid lifts the cover off the intake to the forced air draft blower. The solenoid is
controlled by the damper thermostat. It should lift the cover when the forced air blower
comes on and drop the cover after the blower goes off. If the solenoid does not drop
the cover when the blower goes off, the solenoid should be replaced. The forced air
draft intake cover must be in place when the blower is not running or the heater will
overheat and cause excessive wood usage.
FORCED AIR DRAFT BLOWER, P/N H2002.16(28)
The Hardy Hydronic Heater must be installed outdoors to maintain proper air for
combustion. The draft blower will draw fresh air from under the outer hull and from
around the cracks of the door jamb and back door. If the blower wheel or the intake to
the blower is clogged, the blower will not deliver the proper amount of air to the fire.
The blower can be disassembled and cleaned. Be sure to seal the blower motor back
to the blower housing if the blower is disassembled. The motor should be oiled at the
beginning of each heating season. When the heater is not in use, the power cord for
the blower should be unplugged.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 31
SECTION VII
HEATER MAINTENANCE
7-1
Preventative Maintenance
Preventative maintenance can provide improvements in system performance as well
as a marked reduction in comfort complaints. The customer should preform
preventative maintenance actions to avoid unnecessary shutdown time and save
repair expenses.
Preventative Maintenance Checklist:
Ground Fault Interrupter Receptacle > Test monthly to insure proper and safe
operation. (a) Check with a circuit tester to determine if the polarity is correct. (b) Press
the test button, the reset button should pop out indicating the interrupter has tripped.
Press the reset button to restore to normal operation.
Heater Piping > Check all piping occasionally on back of heater for any possible water
leaks. Water leaks on heater components can cause electrical shorts, damage to
component parts and insulation.
Low Water Light >Check the low water warning light each week for proper operation to
avoid low water or over filling in heater with electric make-up water systems. See
service information (section VI) in owners manual for approved procedures.
Ash Bin > Keep ash bin from ash buildup. Remove ashes before they build up to the
level of the grates. This will restrict proper air flow and cause the grates to warp. Leave
at least 1/2” to 1” of ashes in bottom of ash pan to protect the bottom from burnout.
Damper/Draft System and Smoke Stack > Check at least every two weeks for build up
of ash, tar, or any other material that could restrict the amount of air flow required. Oil
the blower motor bearings prior to each heating season with 10 to 20 drops of electric
motor oil.
Door Seals > Check firebox door and ash door seals occasionally for damage or
obstructions that would affect an airtight seal.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 32
7-2
Preseason Maintenance
The Hardy Hydronic Heater is designed for ease of operation and service. There is
maintenance that has to be done for proper operation of your new unit. Each year,
before the heating season begins, you should check your heater to insure that
everything is ready for the heating season.
ELECTRIC MAKE-UP WATER – Turn on the cold water supply to the heater. Plug in
the power cord. Check the float switch operation by lifting up and pushing down on the
float. When you push the float down it should activate the electric water solenoid and
allow water to enter the heater water tank. When you lift up on the float it should
deactivate the water solenoid, stopping the water. Also make sure the float will float up
on its own when the water level is high enough. After checking the float and solenoid
operation, you should be able to determine if either of these components will require
replacement. Next, turn off the cold water supply and remove the screen filter. This
filter is located in the 1/2” x 1/4” brass bushing between the 1/2” brass ball valve and
the electric solenoid valve. Clean this filter or replace it. Reinstall the screen filter,
making sure the cone point of the screen is pointing towards the incoming water. Turn
the cold water supply back on.
WATER QUALITY – The Hardy Hydronic Heater is designed not to lose heater water
through evaporation. At times during the year, accidental overheating can occur, and
the water will evaporate. The evaporation causes a concentration of chlorides (salts)
and other minerals. To protect your heater from this build up of chlorides (salts) and
other minerals, we recommend to drain your heater each year at time of startup for the
heating season and refill with rain water or bottled water with a chloride concentration
of less than 15 parts per million. This will add to the life of your stainless steel tank.
DAMPER AND DRAFT SYSTEM – When you plugged in the power cord, the damper
solenoid should have opened the draft lid on the draft blower. The forced air draft
blower should also have come on. If both of these components are working correctly,
unplug the power cord. Open the clean out lid beside the draft blower and check for
any build up of ash, tar, or any other material that could restrict the amount of
combustion air entering the heater. Check the seal on the clean out lid to assure a
good air tight seal is still established. Lift the damper lid on the draft blower and inspect
the blower wheel for any build up of lint, dust, creosote, or any other substance that
could affect the performance of the draft blower. Spray the damper lid hinge, and the
damper solenoid plunger with WD-40, or its equivalent. Oil the draft blower motor with
electric motor oil, or 10 weight no detergent motor oil. Do no use WD-40, or machine
oil. Check the grates inside the heater to see if there is any ash build up or if the grates
are warped. If a grate does warp, lift that grate up and turn it over. Also at this time
check the smoke stack for blockage, and the flame/baffle in the H4 & H5 models.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 33
7-2
Preseason Maintenance (continued)
WATER PUMP – Unplug the power cord going to the water pump. Close the valve
above the water pump and the return water valve at the bottom of the heater. Remove
the pump motor from the pump housing by removing the four bolts in the pump
housing. Remove the impeller cartridge assembly from the pump housing. Check the
impeller to determine that it is free by spinning the impeller in the cartridge. Check the
pump housing for rust or any other build up that could impede the flow of water.
Reassemble the water pump, making sure the “O” ring in the cartridge is seated right.
Once the pump is reinstalled, open the water valve above the pump and the return
valve.
GASKETS - Check all door seals. To replace a door seal remove the door and frame
from the heater. Pull out old seal and clean the door and frame of all old silicone. Put
two small beads of silicone in the gasket area of the door and install rope into this area
starting at one corner. New rope seals are 5/8” diameter and 64” length for the fire box
door, and 48” length for the ash door. Work the rope down smooth all the way around
the door and cut off excess rope. Fill in the corner gaps with silicone, allow to dry
before seating against the frame. To reinstall the door, clean the frame of the heater of
all old silicone. Put a generous bead of silicone on the heater door frame being sure to
fill the corner joints with the silicone. Reinstall the door into the same screw holes.
Tighten all screws, wipe off any silicone that might have squeezed out.
Check the gasket on the clean out lid on the air tube in back of the heater. To replace
the gasket on the clean out lid first remove old gasket completely. Put a generous
bead of silicone on the back side of the lid where it will be coming into contact with the
square air tube going into the heater. Place a piece of wax paper across the silicone to
prevent it from sticking to anything other than the lid. Spray the wax paper with a
misting of water to allow the paper to become more flexible. Close the lid down gently
onto the air tube, lift back up to check for a indent into the paper and silicone seal. If
indent has wrinkles in the paper gently lift the paper away from the silicone to
straighten back out and set lid back down to form the seal again. You may have to do
this step a couple of times until you get a good seal. Once the seal has been formed,
let the lid rest on the air tube until silicone seal has cured.
7-3
In Season Maintenance
WATER LEVEL- Monitor water level in the heater by removing the condenser stack
and looking inside the water tank. You should be able to see the low water switch
inside the splash guard in the water tank. The low water switch is a horizontally
mounted reed switch that has a magnet in the floating portion of the switch. When the
water level is high enough to raise the magnet up off of the reed switch this allows the
switch to break contact, and discontinues power to the water solenoid and low water
light. When the water level drops the floating portion of the low water switch the
magnet will once again come into close proximity of the reed switch and close the
contacts allowing power to be applied to the water solenoid and low water light. On
models that do not have automatic fill the low water switch turns on power to the low
water light only. The heater water level will need to be corrected manually by adding
water to the condenser tank area until the low water light goes out. It is recommended
that you check this water level at least once a week while the heater is in operation.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 34
7-3
In Season Maintenance
ASH REMOVAL- Ashes must be removed from inside the heater on a routine basis.
Excessive ash buildup inside the ash box will reduce heating efficiency and can lead to
premature breakdown or warp age of the grates. When you remove the ashes, leave
approximately 1” of ash in the ash bin, this will give the coals that fall through the
grates a bed to fall on and prevent the coals from warping the ash pan itself. The build
up of ashes in the firebox should be checked at least once a week. Allow the fire to
burn down until the grates can be seen. This insures that the grates are clear. If the
grates do warp slightly they can be flipped and allowed to straighten back out.
AIR PASSAGE- After you remove the ashes from the heater you need to check the
total air passage (from blower to stack ). Unplug the two wire power cord so the blower
will not accidentally come on while you are checking it. Raise the damper lid up on the
blower to check the blower wheel for any build up or obstructions. Raise the cleanout
lid on the main air tube going into the back of the heater. Check the clean out for
blockage, such as creosote build up or ashes. Check the grates for build up on top of
grates that could block the flow of air to the fire. Check the smoke stack for creosote
build up. In the H4 and H5 models there is a baffle plate mounted in the fire box
directly below the smoke stack. This baffle plate can be removed for cleaning. This
baffle plate is laying across two (2) pipes in the top of the fire box and can be slid to
either side for removal. Any obstruction of the exhaust gases or the supply air to the
fire will make the heater not perform correctly. When finished checking and/or cleaning
plug in the power cord to put heater back in service.
7-4
Post Season Maintenance
Preplan when you want to shut your system down. Allow your heater to burn
completely out of fuel and cool down. Turn off power to the heater. Unplug all power
cords in the back of the heater. Clean out all ashes from the ash bin area and any build
up of ashes and creosote from the firebox area. Remove the grates and support
beams to facilitate in this cleaning. Once the heater has been cleaned out, replace the
support beams and grates back into the heater. On the H4 and H5 models remove
and clean the baffle plate in the top of the fire box, and clean out the smoke stack.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 35
Section VIII
APPENDIX
8-1
GENERAL TROUBLE SHOOTING GUIDE
WARNING:
When working with electrical circuits, use caution to avoid electrical shock
Service on this heater should only be performed
by a qualified service technician.
Complaint
Area of Trouble Possible Cause
Ground
Fault
Interrupter
Receptacle
Tripping
Ground Fault
Interrupter
Receptacle
Corrective Action
1. Moisture in receptacle 1. Remove cover and
2. Receptacle not
check for moisture
grounded properly.
inside box. If moisture
is present, use blow
dryer to dissipate.
2. Remove cover and
check the bare copper
wire connected to the
green screw for secure
attachment. Test
receptacle for proper
operation.
Forced air draft Moisture or corrosion in
electrical connections or
blower and
windings
damper
solenoid.
Check electrical
connections and windings
for moisture or corrosion.
Clean or dry and then test
for proper operation.
Check electrical
connections, capacitor and
motor winding for bad
connections or corrosion.
Clean, dry and then test
for proper operation.
Pump motor
Corrosion in motor
electrical connections or
windings
Liquid level
switch, low
water light, and
water solenoid
valve
Bad connections possibly Check electrical
to ground
connections for bad
connections or corrosion.
Clean, dry and then retest
for proper operation.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 36
8-1
GENERAL TROUBLE SHOOTING GUIDE
Complaint
Area of Trouble
Possible Causes
No Heat
Pump performance
Unplug pump and bypass relay by tying relay
wires #4 and #6 together. Plug pump back in.
Main power
supply and
ground fault
interrupter
receptacle
“OK”
Pump does not run
1. Defective pump
cartridge
Water
temperature
is “HOT”
HARDY MANUFACTURING CO., INC
2. Defective pump
capacitor
3. Defective pump
motor winding
Corrective Action
1. Unplug pump. Remove
pump. Pull cartridge
from pump and spin
impeller by hand. If
impeller will not spin,
replace cartridge.
2. Use ohm meter. When
the meter is connected
to the capacitor, the
needle should jump
towards “0” ohms and
slowly drift back to
infinity. Replace if
defective.
3. Disconnect the wires
connected to the motor
terminals to test the
motor independent of
electrical connections.
Check for ground and
continuity with ohm
meter. The insulator of
the windings should
show no breakage. If it
does, replace pump
(MODEL H2, H3, H4, & H5)
PAGE 37
8-1
GENERAL TROUBLE SHOOTING GUIDE (continued)
Complaint
Area of Trouble
Possible Cause
No Heat
Pump Performance
Unplug pump and bypass relay by tying relay
wires #4 and #6 together. Plug pump back in.
Main power
supply and
ground fault
interrupter
receptacle
“OK”
Pump does run
1. Defective 24 volt 1. Located at existing
transformer
central unit. If 120/230
volts is being supplied
to primary side check
for 24 volts on
2. Defective wall
secondary. If 24 volts
thermostat
not present, replace
(heater)
transformer.
2. Located inside home.
Remove cover. Check
for 24 volts. Level the
3. Defective low
mounting base. Blow
temperature
dust from sensing
sensor
bimetal. Adjust heat
anticipator. See
4. Defective pump
owners manual
relay
connection
instructions.
3. If heater is up to
temperature (over 140°
f.), remove wires on
sensor and connect to
each other to bypass.
If pump runs replace
low temperature
sensor.
4. Check relay terminals
#7 & #8 for 24 volts. If
24 volts is present, use
ohm meter to check
contacts. Connect ohm
meter to terminals #4
& #6. If no reading
replace relay.
Water
temperature
is “HOT”
HARDY MANUFACTURING CO., INC
Corrective Action
(MODEL H2, H3, H4, & H5)
PAGE 38
8-1
GENERAL TROUBLE SHOOTING GUIDE (continued)
Complaint
Area of Trouble
Possible Cause
No Heat
Aqua stat
Main power
supply and
ground fault
interrupter
receptacle
“OK”
Defective Aqua stat Unplug power cord.
Connect the two wires on
the aqua stat together.
Plug in power cord. If
blower and damper
solenoid operates, replace
aqua stat.
Damper solenoid
Defective damper
solenoid
When bypassing aqua
stat, if solenoid does not
lift the lid off the intake to
the forced air draft blower,
replace the solenoid.
Forced air draft
blower motor
Defective blower
motor
1. Defective
electrical wiring
2. Air passage
stoppage
3. Blower wheel
clogged
1. Make sure all
connections are
secure.
2. Clear air passages in
cleanout and damper
blower outlets.
3. Clear blower wheel of
any lint, ashes or
creosote buildup.
Ash bin
Ash buildup in ash
bin
Clean out ash bin. Ash
bin should be cleaned out
each week. Ash buildup
on grates can cause
grates to warp. If grates
warp they can be turned
over and allowed to
straighten. When
removing ashes, leave at
least 1” of ashes in
bottom of ash pan.
Clean heater stack of
any ash and creosote
buildup. On H4 models
make sure the baffle
plate is clear of ash and
creosote buildup. Make
sure baffle is in place,
otherwise heat will be
lost up the stack.
Water
temperature is
“COLD”
Heater stack
HARDY MANUFACTURING CO., INC
Ash and creosote
buildup
Corrective Action
(MODEL H2, H3, H4, & H5)
PAGE 39
8-1
GENERAL TROUBLE SHOOTING GUIDE (continued)
Complaint
Area of Trouble
Possible Cause
Corrective Action
No Heat
Water supply
Defective Liquid
Level Switch.
Liquid level switch
controls the water level
indicator light and water
solenoid valve. Check
switch with hand by
raising or lowering float
inside the condenser
area. If water solenoid
does not click and light
does not go on and off,
replace the liquid level
switch.
Water solenoid
valve
1. Defective
solenoid valve
1. If water solenoid valve
does not click when
checking the liquid
level switch, but level
indicator light does
come on – replace
solenoid valve.
2. Remove filter screen
from 1/2” bushing in
end of 1/2” ball valve,
clean or replace.
Water Level is
“LOW”
Water
temperature is
“HOT”
Main power
supply and
Ground Fault
Interrupter
Receptacle
“OK”
2. Water filter
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 40
8-1
GENERAL TROUBLE SHOOTING GUIDE (continued)
Complaint
Area of Trouble
No Heat
1. Pump not
Water not
operating
circulating through
2. Inline valves
the heat loop
closed/bad
3. Air trapped in
plumbing
4. Scale deposits in
hot water coil
reducing water
flow and
restricting heat
transfer
5. Air lock in hot
water coil
Blowing cold
air in house
Water
temperature is
“HOT”
Power “OK”
Possible Cause
Excessive wood Heater water boils 1. Doors open
usage
2. Defective door
(Symptom – pop off
seals
or
valve is relieving)
3. Damper blower
lid stuck open
Overheating
4. Damper aqua
(boiling)
stat defective
5. Water lines /
connections
leaking
HARDY MANUFACTURING CO., INC
Corrective Action
1. See area of trouble:
“Pump Operation”
2. Open or replace
valves
3. Bleed lines if air is
trapped (non
pressured lines require
pump to be running).
4. Disconnect the inlet
and outlet of the hot
water coil and clean
with a scale remover
solution.
5. Bleed air from hot
water coil
1. Close all doors and
make sure they are
securely fastened.
2. If the seal is bad it will
need replacing. Call
your local Hardy
Dealer for parts. See
Owners Manual for
replacing door seals.
3. Unplug blower motor.
Check lid and blower
for creosote buildup.
Remove blower,
dissemble, clean, and
oil.
4. Check temperature
setting on aqua stat.
Should be 170ºF. If
aqua stat is allowing
blower to run until
water boils, replace
aqua stat.
5. Repair or replace all
lines or connections
that are leaking.
(MODEL H2, H3, H4, & H5)
PAGE 41
8-1
GENERAL TROUBLE SHOOTING GUIDE (continued)
COMPLAINT
AREA OF TROUBLE
POSSIBLE CAUSE
Excessive
wood usage
Excessive wood
usage
Or
(Symptom;
pop off valve is
relieving
heater water
overflowing)
1. If Pop off valve is
1. Pop off valve
relieving for no
2. Defective liquid
reason, replace pop
level switch
off valve.
3. Solenoid valve
stuck or corroded 2. Check liquid level
switch float for
4. Domestic hot
position, float should
water heat
float up as the heater
exchanger coil
fills with water. Check
leaking
switch by pivoting float
up and down to see if
solenoid clicks and
light goes on and off,
if not replace switch.
3. If solenoid does click
and the heater still
overflows, it could be
stuck in open position,
- remove and clean or
replace.
4. Disconnect line to the
electric water solenoid
and turn off valve to
system fill to assure
no water enters tank
from the fill system. If
heater tank still
overfills then remove
heater hull and lid to
check domestic water
coil for leaks, repair or
replace.
Overheating
(boiling)
HARDY MANUFACTURING CO., INC
CORRECTIVE ACTION
(MODEL H2, H3, H4, & H5)
PAGE 42
8-1
GENERAL TROUBLE SHOOTING GUIDE (continued)
COMPLAINT
AREA OF TROUBLE
POSSIBLE CAUSE
CORRECTIVE ACTION
Improper
Burning
Grates
Grates stopped up
Clear grate of ash
buildup. If grates are
warped, turn over.
Air intake
Damper blower
clogged
Clean damper blower
assembly.
Air tube inspection
lid
Air tube clogged
Lift inspection lid and
cleanout all obstructions.
Smoke Stack
Smoke stack
stopped up
Remove smoke stack,
check flue out of top of
heater, clean both flue
pipe and smoke stack.
Baffle
(Model H4 & H5
Only)
Baffle stopped up
Remove baffle through
the fire box door, clean
baffle and flue area.
Fire
Fire going out
If fire goes completely out
remove one screw in
blower lid.
Forced air blower
running but no draft
1. Solenoid not
1. Replace solenoid.
lifting lid
2. See excessive wood
2. Creosote buildup
usage.
Fire box
1. Initial or yearly
start up
2. Green wood
Moisture In
fire box
HARDY MANUFACTURING CO., INC
1. Fire box walls will
sweat and water will
run down sides, this
should clear up in
about a week.
2. Green wood will
create moisture at any
time.
(MODEL H2, H3, H4, & H5)
PAGE 43
8-2
Circulator Maintenance Instructions
Step #
Operation Description
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
!
Testing/Replacing Pump Cartridge
1
Close the pump inlet and return ball valves to prevent
water flow.
2
Loosen and remove the four(4) 7/16" screws from the
pump motor housing.
3
Gently pull the pump motor housing toward you and turn
so you can view pump impellar.
4
Rotate the pump impellar by hand. If the impellar will
not spin freely then replace the cartridge.
5
Reassemble in reverse order.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 44
8-2
Circulator Maintenance Instructions (continued)
Step #
Operation Description
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
!
Testing Pump Capacitor
1
Remove top cover to expose electrical connections.
2
If using an analog ohm meter, check the resistance
across the two capacitor leads. The meter should
immediately read "0" ohms then slowly drift to infinity.
Reverse the test leads and check meter reading. The
test procedure is the same for a digital multimeter
except the meter will show some resistance then return
to "OL" (open line). To replace capacitor, cut away
existing wire nut connectors. Strip leads and connect
with wire nut connector suitable for two(2) 16 AWG
wires.
3
Replace cover.
1
Testing Pump Motor Winding
Disconnect power cord from motor wiring. Using an
ohm meter or continuity tester, check the continuity
across each power wire and also check each power
wire to ground. If the the pump does not show continuity
across the two power wires or if either power wire
shows continuity to ground the winding is defective and
the pump should be replaced.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 45
8-3
Damper Solenoid Replacement Instructions
Step #
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
1
Remove female quick connect terminals from damper
solenoid.
2
Using needle nose pliers, open top link in lift chain and
remove from solenoid.
3
Using a 5/16" wrench or other suitable tool, remove the
three screws holding the Damper Solenoid to the
electrical panel.
4
Install new damper solenoid in reverse order. Make
sure chain is straight above the flapper lifter as shown.
There should be tension in the chain when the flapper is
in the down position.
HARDY MANUFACTURING CO., INC
Remove
Three
Screw s
Chain should be
straight above
Damper Flapper.
(MODEL H2, H3, H4, & H5)
PAGE 46
8-4
Low Water Switch Replacement Instructions
Step #
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
1
Open the tank drain valves until the water level is below
the float switch.
2
Remove plastic wire tie located near float switch. Cut
the switch wires approx. 6 inches from the rear of the
the float switch. On models with the automatic water fill
option do not cut the power wires for the solenoid.
Using an adjustable wrench or other suitable tool
remove the float switch from the heater.
3
Looking at the wrench flats on the switch there are two
directional arrows located on the side as shown. For
the switch to operate correctly it will have to be oriented
with the arrow pointed down when installed.
4
Apply pipe joint compound liberally around the threads
of the switch. Using an adjustable wrench or other
suitable tool install the switch in the tank. Do not
overtighten. Make sure the switch is oriented with the
arrow pointing down.
HARDY MANUFACTURING CO., INC
Open these valves
Remove plastic
w ire tie.
Cut w ires approx. 6"
from rear of switch.
Arrow
(MODEL H2, H3, H4, & H5)
PAGE 47
8-4
Low Water Switch Replacement Instructions (continued)
Step #
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
5
Connect new switch wiring to existing wiring using
suitable wire nut.
6
Reconnect power to furnace. On models with the
automatic water fill option allow the unit to fill above the
float switch. If the automatic water fill and low water
indicator mounted on side of hull does not turn off when
the water reaches the correct level, the switch is
possibly not oriented correctly. On units without the
automatic water fill option, fill the tank until the water
level is above the float switch. The low water light
mounted on the left side of the hull should turn off when
the water is at this level. If the light does not go out the
switch is possibly oriented incorrectly.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 48
8-5
Draft Blower Replacement Instructions
Step
Operation Description
!
1
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
Remove the plastic cable tie and disconnect the blower
power wires as shown. Remove damper lifter ring from
blower flapper lifter. Using a 5/16" wrench or other
suitable tool, remove the blower electrical box cover.
Damper Lif ter
Ring
Plastic cable tie
and electrical
connections.
Blower electrical
box cov er
2
Slide a flat head screwdriver into plastic romex
connector and lift up wedge clamp. Pull blower power
wires through clamp. Remove clamp by pressing on
locking tang with a flat head screwdriver and pulling
away from blower.
3
Loosen and remove the three flange screws. Remove
blower from heater.
4
Place new flange gasket onto blower flange. Align
holes on gasket with holes in flange. Start inner screw
but do not tighten.
5
Position blower over gasket. Tighten inner screw to
hold blower in position, then install and tighten the two
outer screws.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 49
8-5
Draft Blower Replacement Instructions (continued)
Step
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
6
Install damper lifting ring into the damper lid as shown.
7
Using a 5/16" wrench or other suitable tool, remove the
cover from the blower electrical box and set aside.
Using pliers or other suitable tool, remove the right
knockout and install the plastic romex connector.
8
Push blower power wires through connector. Replace
blower electrical box cover. Using pliers press the
wedge clamp into place.
9
Connect power wires and install plastic cable tie if
available.
10
Verify blower is firmly attached to flange and damper
flapper will lift freely.
11
Reconnect power to furnace.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 50
8-6
Automatic Water Fill Replacement Instructions
Step #
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
1
If you are replacing the water fill solenoid then cut wires
to automatic water fill approx. 4" to 6" from rear of fill
solenoid as shown. Cut only if solenoid is to be
replaced.
2
Firmly pull solenoid up and away from switch post as
shown. If you are replacing the solenoid then discard.
Otherwise set the solenoid aside for later installation. If
you are not replacing the water fill valve then skip to
step # 8.
3
Using an adjustable wrench loosen and remove the flex
line fitting from solenoid assembly and set aside.
4
Using an adjustable wrench or other suitable tool
remove the automatic water fill assembly from heater.
Remove the brass elbow, 1/2"x1/4" bushing and 1/4"
close nipple from the assembly. These parts will be
reused on the new assembly.
5
Clean the screen inside the 1/2"x1/4" brass bushing
prior to re-installation using warm soapy water.
HARDY MANUFACTURING CO., INC
Cut wires
here
(MODEL H2, H3, H4, & H5)
PAGE 51
8-6
Automatic Water Fill Replacement Instructions (continued)
Step #
Operation Description
!
6
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
Note: The automatic water fill valve has an arrow
stamped in the housing showing the direction of flow.
The valve has to be installed with the arrow in the
correct direction for the valve to operate properly.
Direction of Flow
7
Apply pipe thread sealant to the threads of the fitting
removed in step 5. Install the fittings and the new valve
assembly on the heater as shown. Care should be
taken to make sure no excess pipe sealant gets into the
screen during assembly. This wil result in reduced water
flow. The brass elbow should point slightly forward.
8
Using a pipe wrench or other suitable tool turn the tee
approx. 1/4 turn counter-clockwise until the assembly is
parallel with the rear of the furnace. Reinstall the flex
line fitting and tighten hand tight plus approx. 1/2 turn.
Do not over tighten the flex line to prevent damage to
the inner bushing.
9
Slide solenoid over valve stem and press firmly into
place. Make sure spring retainer clip on solenoid
latches into groove in top of valve stem.
10
If replacing the solenoid strip wires approx. 1/2" and
connect using wire nut suitable for 2 #16 AWG wires
(orange) as shown. These wires are not polarity
sensitive.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 52
8-7
Honeywell Aqua Stat Replacement Instructions
Step #
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
1
Using a 1/4" nut driver or flat head screwdriver loosen
the cover screw located at the bottom of the thermostat
and then remove cover.
2
Loosen the two screws on the wire clamp and then
using a flat head screwdriver depress the locking tabs
holding the clamp in place. Gently pull the wire clamp
down and away from the thermostat body.
3
Pull on the thermostat capillary tube to make sure that
the bulb has not been damaged during heater
operation. Make sure the bulb is not lodged in the well
fitting. If the bulb is lodged the well fitting will have to be
replaced.
4
Fold back the terminal block protector. Loosen the two
screws on the terminal block and remove the two
thermostat wires. Pull the wires through the wiring hole
and lay aside.
5
Loosen the two screws on the thermostat clamp. Gently
lift the thermostat away from the well fitting. If the bulb is
lodged in the well fitting cut the capillary tube using a
wire cutter or other suitable tool. If the well fitting does
not require replacement then skip to step # 10.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 53
8-7
Honeywell Aqua Stat Replacement Instructions (continued)
Step #
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
6
Open the heater tank drain valves and allow the furnace
tank to drain until the tank water level is below the
thermostat level.
7
Using an adjustable wrench remove the well fitting from
the rear of the furnace.
8
Apply pipe joint compound to the threads of the new
well fitting and then screw the fitting into the rear of the
furnace. Use an adjustable wrench to tighten the fitting.
9
Remove the cover from the new thermostat. Loosen the
two screws on the thermostat clamp. Make sure the
clamp is loose enough to slide over the notch in the well
fitting.
10
Slide the bulb into the well fitting. Position the
thermostat so that the thermostat well hole is centered
over the well, the thermostat is perpendicular to the
ground and the clamp is engaged in the groove of the
well fitting. Tighten the two well clamp screws. Do not
over tighten the clamp screws.
HARDY MANUFACTURING CO., INC
Open these valves
(MODEL H2, H3, H4, & H5)
PAGE 54
8-7
Honeywell Aqua Stat Replacement Instructions (continued)
Step #
Operation Description
!
Visual Aids/Comments
Hazardous Voltage! Disconnect Power to
Heater prior to performing this
maintenance operation.
11
Pull thermostat wires through wiring hole. Place
terminals on studs in terminal block and tighten in place.
Using a flat head screwdriver or other suitable object lift
the locking tabs on the wire clamp then push the wire
clamp into the wiring hole. Using a flat head
screwdriver tighten the two clamp screws.
12
Verify the thermostat temperature setting is correct.
The correct value is written on the front cover. The dial
can be adjusted using a flat head screwdriver.
13
Replace the cover and tighten the cover screw.
14
Reconnect power to furnace. If the water level was
lowered to install a new well fitting, MAKE SURE THE
FURNACE IS FILLED WITH WATER TO THE
CORRECT LEVEL BEFORE OPERATING
HEATER.
HARDY MANUFACTURING CO., INC
(MODEL H2, H3, H4, & H5)
PAGE 55